This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A166723 #11 Aug 03 2023 10:12:43
%S A166723 1,44,1892,81356,3498308,150427244,6468371492,278139974156,
%T A166723 11960018888708,514280812214444,22114074925221092,950905221784506956,
%U A166723 40888924536733798162,1758223755079553280288,75603621468420789304176
%N A166723 Number of reduced words of length n in Coxeter group on 44 generators S_i with relations (S_i)^2 = (S_i S_j)^12 = I.
%C A166723 The initial terms coincide with those of A170763, although the two sequences are eventually different.
%C A166723 Computed with MAGMA using commands similar to those used to compute A154638.
%H A166723 G. C. Greubel, <a href="/A166723/b166723.txt">Table of n, a(n) for n = 0..500</a>
%H A166723 <a href="/index/Rec#order_12">Index entries for linear recurrences with constant coefficients</a>, signature (42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, -903).
%F A166723 G.f.: (t^12 + 2*t^11 + 2*t^10 + 2*t^9 + 2*t^8 + 2*t^7 + 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(903*t^12 - 42*t^11 - 42*t^10 - 42*t^9 -42*t^8 -42*t^7 -42*t^6 - 42*t^5 - 42*t^4 - 42*t^3 - 42*t^2 - 42*t + 1).
%t A166723 CoefficientList[Series[(t^12 + 2*t^11 + 2*t^10 + 2*t^9 + 2*t^8 + 2*t^7 + 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(903*t^12 - 42*t^11 - 42*t^10 - 42*t^9 - 42*t^8 - 42*t^7 - 42*t^6 - 42*t^5 - 42*t^4 - 42*t^3 - 42*t^2 - 42*t + 1), {t, 0, 50}], t] (* _G. C. Greubel_, May 24 2016 *)
%t A166723 coxG[{12,903,-42}] (* The coxG program is at A169452 *) (* _Harvey P. Dale_, Aug 03 2023 *)
%K A166723 nonn
%O A166723 0,2
%A A166723 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009